降雨类型对北方土石山区坡面土壤侵蚀的影响

发布时间：2018-06-11 15:58

本文选题：土壤 + 侵蚀　；参考：《农业工程学报》2017年24期

【摘要】：该文基于北京市房山区蒲洼径流小区2013-2015年观测的105场自然降雨,采用实测水文数据与WEPP模型模拟降雨侵蚀过程相结合的方法,对比了北方土石山区不同雨型下的坡面土壤侵蚀差异。结果表明:1)自然降雨中,单场降雨的侵蚀能力表现为B型雨(低频率、短历时、中雨量、大雨强)A型雨(中频率、长历时、大雨量、中雨强)C型雨(高频率、中历时、小雨量、小雨强),其中,侵蚀性降雨中A型雨降雨频率最高、对研究区土壤侵蚀的累计贡献率最大;而C型雨几乎不会引发土壤侵蚀。2)诱发北方土石山区棕壤坡面土壤侵蚀的临界雨量为8 mm、临界雨强为9.5 mm/h。3)利用WEPP模型通过设置最大30 min雨强I30出现的不同时间将3类雨型进一步划分为4个子雨型,结果表明同一雨强出现的降雨时序差异会影响土壤侵蚀的发生程度,且子雨型下土壤侵蚀量整体表现为递增型峰值型递减型均值型,其中A型雨4个子雨型下侵蚀量差异最显著。研究结果可为北方土石山区棕壤坡面土壤侵蚀预报模型的建立及土壤侵蚀防治提供参考依据。
[Abstract]:Based on 105 natural rainfall observed in Puwa runoff area of Fangshan District in Beijing from 2013 to 2015, the method of combining measured hydrological data with WEPP model to simulate rainfall erosion process is used in this paper. The difference of soil erosion on slope under different rainfall patterns in the northern earth-rock mountain area was compared. The results show that the erosive capacity of single rainfall is B type rain (low frequency, short duration, moderate rainfall, heavy rain intensity A type rain (medium frequency, long duration, heavy rainfall, moderate rain intensity, low frequency, medium duration, small rainfall), in natural rainfall), the erosive ability of single rainfall is B type rain (low frequency, short duration, moderate rainfall, heavy rain) (medium frequency, long duration, heavy rainfall, moderate rain, moderate duration, small rainfall). The frequency of A type rain is the highest in the erosive rainfall, and the cumulative contribution rate to soil erosion is the largest in the study area. The critical rainfall of 8mm and the critical rain intensity of 9.5 mm / h. 3) by setting up the maximum 30 min rain intensity I 30, the critical rainfall of brown soil slope in northern China is 8 mm and 9.5 mm 路h. 3) by setting up the maximum 30 min rain intensity I 30 at different times. The three types of rain are further divided into 4 sub-rain types, The results showed that the rainfall time series difference of the same rainfall intensity would affect the occurrence degree of soil erosion, and the soil erosion amount under the subrain type showed the increasing peak value decline type mean value as a whole. There was the most significant difference in the amount of erosion under the four sub-rain patterns of A type rain. The results can be used as a reference for the establishment of soil erosion prediction model and soil erosion prevention and control on brown soil slope in northern China.
【作者单位】：北京林业大学水土保持学院重庆缙云山三峡库区森林生态系统国家定位观测研究站;北京市水土保持工程技术研究中心;
【基金】：中央高校基本科研业务费专项资金资助(2015ZCQ-SB-01)
【分类号】：S157.1

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